JPH01122196A - Circuit substrate - Google Patents

Abstract

PURPOSE:To protect an electronic part from noises from the outside by forming a closed thin film pattern composed of a superconductive substance and shaping or mounting the electronic part into the thin-film pattern. CONSTITUTION:Closed thin-film patterns (superconductive thin-films) 4 consisting of a superconductive substance are shaped onto an insulating substrate 5, insulating film 3 are formed onto the superconductive thin-films 4, and terminal electrodes 1 are shaped so as to be superposed on the insulating films 3, and a thick-film resistor 2 is formed. Consequently, even when magnetic flux is applied, currents are made to flow through the ring shaped superconductive thin-films 4, and the penetration of magnetic flux is prevented, thus reducing intrusion to the thick-film resistor 2. Accordingly, an electronic part is formed or mounted into a thin-film 4 ring, thus lowering noises generated by magnetic flux.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a circuit board used for hybrid integrated circuit boards, printed circuit boards, and the like.

BACKGROUND OF THE INVENTION A conventional circuit board will be described below with reference to the drawings. FIGS. 6(a) and 6(b) are a partially enlarged plan view and a sectional view of a conventional circuit board. In FIG. 6, 5 is an insulating substrate made of alumina, etc., 2 is a terminal electrode formed by firing copper paste or silver paste, and 2 is a thick film resistor. Note that there are enlarged or reduced portions in the following drawings, and this is particularly noticeable in the film thickness direction.

Furthermore, the term "thin film" as used herein includes not only a thin film formed by a vapor deposition technique such as sputtering, but also a so-called normal film formed by a screen printing technique or a coating technique.

As is clear from FIG. 6, circuit patterns such as terminal electrodes 1 are formed on the insulating substrate 5, and electronic components such as the thick film resistor 2 are formed or mounted.

Problems to be Solved by the Invention However, when electronic components such as thick film resistors are formed on a conventional circuit board, it is difficult to avoid the influence of magnetic flux generated from other electronic components, as shown in FIG. do not have.

The magnetic flux generates voltage or current within the electronic component, resulting in noise. Therefore, when forming or mounting electronic components on a conventional circuit board, the above-mentioned noise countermeasures are required. The above-mentioned noise countermeasures required extremely advanced technology and experience.

In view of the above problems, the present invention provides a substrate that is less susceptible to external influences such as noise.

Means for Solving the Problems To solve the above problems, the circuit board of the present invention forms a closed thin film pattern made of a superconducting material on an insulating substrate, and forms or mounts electronic components within the thin film pattern. It is characterized by this.

Function The present invention forms a thin film ring made of a superconducting material on an insulating substrate. It is impossible for magnetic flux to penetrate the Wi film ring. Therefore, by forming or mounting electronic components within the thin film ring, noise generated by magnetic flux can be significantly reduced.

EXAMPLE Hereinafter, an example of the circuit board of the present invention will be described with reference to the drawings.

FIGS. 1(a) and 1(b) are a partially enlarged plan view and a sectional view of a circuit board according to a first embodiment of the present invention. In Fig. 1, 4 is a thin film pattern made of superconducting material (hereinafter referred to as
It is called a superconducting thin film) and has a closed ring-shaped pattern. Further, 3 is an insulating film.

As is clear from FIG. 1, superconducting thin film 4 is placed on insulating substrate 5.
An insulating film 3 mainly composed of glass or the like is formed on the superconducting thin film 4. Furthermore, a terminal electrode 1 obtained by firing copper paste or silver paste is formed so as to overlap with the insulating film 3, thereby forming a thick film resistor 2.

In the first embodiment of the present invention, as shown in FIG. 2, even when magnetic flux 9 is applied, current flows through the ring-shaped superconducting thin film 4, and in order to prevent the magnetic flux from entering, the penetration into the thick film resistor 2 is significantly reduced. reduced, so that almost no noise occurs.

Almost the same effects can be obtained in the following embodiments.

FIG. 3(b) is a partially enlarged plan view and cross-sectional view of a circuit board in a second embodiment of the present invention. In FIG. 3, 6 is a chip component such as a chip capacitor, a chip resistor, is solder.

In the second embodiment, a superconducting thin film 4 is formed similarly to the first embodiment, and a chip component 6 is mounted within the superconducting thin film 4.

FIG. 4B is a partially enlarged plan view and cross-sectional view of a circuit board in a third embodiment of the present invention. In FIG. 4, 8 is a coating film made of metal, glass, resin, or the like.

The difference between the first embodiment and the third embodiment is that the superconducting thin film 4 is covered with a coating film 8. By adopting the above-mentioned configuration, the superconducting thin film 4 can be protected from external mechanical stress, and since it is isolated from the outside air, it can maintain a chemically stable state for a long period of time. can.

In the embodiment of the present invention, the insulating film 3 is formed on the superconducting thin film 4, and the terminal electrode 1 is formed on the insulating film 3, but the present invention is not limited to this. It is sufficient to form four patterns. For example, Figure 5 (
a) (As shown in bl, a superconducting thin film 4 may be formed on the insulating film 3. Also, in the above embodiments, as the superconducting material, for example, a so-called room temperature superconductor may be used,
Alternatively, use a material with a superconducting critical temperature between room temperature and the boiling point of liquid nitrogen and cool it with liquid nitrogen (not shown), or use a material with a superconducting critical temperature below the boiling point of liquid nitrogen and cool it with liquid helium. (not shown). Examples of room-temperature superconductors include strontium (Sr), barium (Ba), and indium (Y) as compositions.
There is a ceramic oxide containing copper ((:u)) in a ratio of 1:l:l:3. An example of its production method includes starting materials such as 5rCO, BaCO, Y,
03. A predetermined amount of each powder of CuO is mixed, pulverized, and fired in air at 920° C. for 5 hours.

This firing and crushing process is repeated three times to improve homogeneity.

After cold compression molding the mixed powder treated in this way, it is produced by firing in air at 1000° C. for 5 hours and slowly cooling.

Effects of the Invention As described above, the circuit board of the present invention forms a closed thin film pattern made of a superconducting material, and electronic components are formed or mounted within the closed thin film pattern. It can protect against noise etc. Therefore, it is only necessary to form a closed thin film pattern in a part of the circuit board where noise countermeasures are required and to form electronic components within the closed thin film pattern, which has the great effect of making circuit design very easy. .

[Brief explanation of the drawing]

1(a) and (b) are a partially enlarged plan view and a sectional view of a circuit board according to a first embodiment of the present invention, FIG. 2 is a sectional view of a circuit board of the present invention, and FIG. 3(a) (b) is a partially enlarged plan view and cross-sectional view of the circuit board in the second embodiment of the present invention, FIG. 4+8) (b) is a partially enlarged plane view of the circuit board in the third embodiment of the present invention 5(a) and 5(b) are a partially enlarged plan view and a sectional view of a circuit board of the present invention, and FIG. 6(al) is a partially enlarged plan view and a sectional view of a conventional circuit board. 7 are cross-sectional views of conventional circuit boards. 1...Terminal electrode, 2...Thick film resistor, 3
...Insulating film, 4...Superconducting thin film, 5.
...Insulating substrate, 6...Chip parts, 7.
...Solder, 8...Coating film, 9...
...magnetic flux.

Claims (2)

[Claims] (1) A circuit board characterized in that a closed thin film pattern made of a superconducting material is formed on an insulating substrate, and electronic components are formed or mounted within the closed thin film pattern. (2) The circuit board according to claim (1), characterized in that a closed thin film pattern made of a superconducting material is coated with metal, glass, or resin.